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    <title>ShellCheck: SC1097 – Unexpected `==`. For assignment, use `=`. For comparison, use `[`/`[[`.</title>
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    <h1>SC1097 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC1097">See this page on GitHub</a>
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    <h2 id="unexpected--for-assignment-use--for-comparison-use-">Unexpected
<code>==</code>. For assignment, use <code>=</code>. For comparison, use
<code>[</code>/<code>[[</code>.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC1097.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="va">var</span><span class="op">=</span>=value</span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<p>Assignment:</p>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC1097.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="va">var</span><span class="op">=</span>value</span></code></pre></div>
<p>Comparison:</p>
<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="SC1097.html#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="bu">[</span> <span class="st">&quot;</span><span class="va">$var</span><span class="st">&quot;</span> <span class="ot">=</span> value <span class="bu">]</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>ShellCheck has noticed that you're using <code>==</code> in an
unexpected way. The two most common reasons for this is:</p>
<ul>
<li><p>You wanted to assign a value but accidentally used
<code>==</code> instead of <code>=</code>.</p></li>
<li><p>You wanted to compare two values, but neglected to use
<code>[ .. ]</code> or <code>[[ .. ]]</code>.</p></li>
</ul>
<h3 id="exceptions">Exceptions:</h3>
<p>If you wanted to assign a literal equals sign, use quotes to make
this clear:</p>
<div class="sourceCode" id="cb4"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb4-1"><a href="SC1097.html#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="va">var</span><span class="op">=</span><span class="st">&quot;=sum(A1:A10)&quot;</span></span></code></pre></div>
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